Manufacturing method of component-embedded substrate and component-embedded substrate

Abstract

The manufacturing method of the embedded substrate of the component includes the steps of providing an intermediate component (2), the intermediate component (2) comprising: an electronic component (10) having a first electrode (11) disposed on a first surface (13); and a first conductive layer (20) disposed on the first surface (13) of the electronic component (10) to cover the first electrode (11); and forming a first insulating resin layer (40) on the first surface (3) of the intermediate component (2). The first conductive layer (20) comprises: a first cured adhesive layer (23) containing a cured adhesive layer (22) comprising conductive particles (21) and a cured adhesive composition; and a first metal foil layer (24) disposed on the first cured adhesive layer (23) and on the side opposite to the electronic component (10). The conductive particles (21) of the first cured adhesive layer (23) electrically connect the first electrode (11) of the electronic component (10) to the first metal foil layer (24).

Description

Technical Field

[0001] This invention relates to a method for manufacturing a component-integrated substrate and the component-integrated substrate. Prior Technology

[0002] Patent document 1 discloses a method for manufacturing a printed wiring board that incorporates electronic components such as IC chips.

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2012-191204

[0004] In conventional manufacturing methods for in-system substrates, as shown in Figures 5(a) and (b), insulating resin layers 102 and 103 are formed on both sides of the stacking direction of the electronic component 101 on which electrodes 101a are provided. Subsequently, as shown in Figures 5(c) and (d), through-hole electrodes 104 and 105 reaching each electrode 101a of the electronic component 101 are formed on each insulating resin layer 102 and 103 by performing laser-based drilling, plating layer formation, and etching-based electrode formation. Furthermore, as shown in Figures 6(a) to (c), by repeatedly performing further forming of insulating resin layers 106 and 107, forming of through-hole electrodes 108 based on laser drilling and plating layer formation, and etching-based electrode formation, an in-system substrate 110 can be formed. However, in the manufacturing method of such a component with a built-in substrate, a large number of processes are performed to form one conductive layer (through-hole electrode), and these processes need to be repeated in order to form multiple conductive layers, making the manufacturing process very complex. Summary of the Invention

[0005] Therefore, the object of the present invention is to provide a method for manufacturing a component-in-the-board substrate that simplifies the manufacturing process, and a component-in-the-board substrate.

[0006] In one aspect, the present invention relates to a method for manufacturing a component-in-the-board substrate. The method includes: step (a) providing an intermediate component, the intermediate component comprising: an electronic component having a first electrode disposed on a first surface; and a first conductive layer disposed on the first surface of the electronic component to cover the first electrode; and step (b) forming a first insulating resin layer on the first surface of the intermediate component. The first conductive layer comprises: a first cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition; and a first metal foil layer disposed on the first cured adhesive layer and on the side opposite to the electronic component. The conductive particles of the first cured adhesive layer electrically connect the first electrode of the electronic component to the first metal foil layer.

[0007] In the manufacturing method of the embedded substrate of this component, the first conductive layer of the intermediate component provided in step (a) is composed of a first cured adhesive layer having a cured adhesive layer containing a composition of conductive particles and a cured adhesive, and a first metal foil layer. The conductive particles of the first cured adhesive layer electrically connect the first electrode of the electronic component to the first metal foil layer. In this way, since the intermediate component including the electronic component can be simplified, the manufacturing method of the embedded substrate of the component can be simplified.

[0008] In the above-described method for manufacturing a substrate embedded in a component, the intermediate member further includes a second conductive layer disposed on a second surface of the electronic component opposite to the first surface, allowing a second electrode to be disposed on the second surface of the electronic component opposite to the first surface. The second conductive layer comprises: a second cured adhesive layer containing a cured adhesive composition comprising conductive particles and a cured adhesive layer; and a second metal foil layer disposed on the second cured adhesive layer on the surface opposite to the electronic component. The conductive particles of the second cured adhesive layer electrically connect the second electrode of the electronic component to the second metal foil layer. In this case, since simplified conductive layers are disposed on both sides of the electronic component, the method for manufacturing a substrate embedded in the component is simplified.

[0009] In the manufacturing method of the aforementioned component-integrated substrate, step (a) of providing an intermediate component may include: a step of preparing an electronic component (a1); a step of preparing a first adhesive film (a2); a step of adhering the first adhesive film to a first side of the electronic component to cover the first electrode (a3); and a step of heat-pressing the first adhesive film onto the electronic component (a5). The first adhesive film has: a first adhesive layer containing conductive particles and an adhesive composition in which the conductive particles are dispersed; and a first metal foil layer disposed on the first adhesive layer and on the side opposite to the electronic component. In the heat-pressing step (a5), by heat-pressing the first adhesive film, the conductive particles of the first adhesive film electrically connect the first electrode of the electronic component to the first metal foil layer, and the adhesive layer of the first adhesive film is cured to become a first cured adhesive layer. At this point, since a conductive layer is formed using an adhesive film containing conductive particles dispersed in the adhesive composition, complex procedures such as laser-based drilling, plating layer formation, and etching-based electrode formation are unnecessary. A conductive layer connecting electrodes separated in the stacking direction can be easily formed. As a result, the manufacturing method of the substrate built into the component can be simplified. Furthermore, the order of steps (a1) to (a3) ​​and (a5) is not limited to the order described above, and the order can be appropriately changed.

[0010] In the manufacturing method of the aforementioned component-integrated substrate, step (a) of providing an intermediate component may include: a step of preparing an electronic component (a1); a step of preparing a first adhesive film and a second adhesive film (a2); a step of attaching the first adhesive film to a first side of the electronic component to cover a first electrode (a3); a step of attaching the second adhesive film to a second side of the electronic component to cover a second electrode (a4); and a step of heating and pressing the first adhesive film and the second adhesive film onto the electronic component (a5). The first adhesive film has: a first adhesive layer containing an adhesive layer comprising conductive particles and an adhesive composition in which the conductive particles are dispersed in the adhesive composition; and a first metal foil layer disposed on the first adhesive layer and on the side opposite to the electronic component. Furthermore, the second adhesive film comprises: a second adhesive layer containing an adhesive layer comprising conductive particles and an adhesive composition, wherein the complex conductive particles are dispersed in the complex adhesive composition; and a complex second metal foil layer disposed on the complex second adhesive layer and on the side opposite to the complex electronic component. Additionally, the order of steps (a1) to (a5) is not limited to the order described above, and the order can be appropriately changed. For example, the order of performing steps (a1) and (a2) is not limited; step (a1) can be performed first, and conversely, step (a2) can be performed first, and furthermore, steps (a1) and (a2) can be performed simultaneously. Similarly, the order of performing steps (a3) ​​and (a4) is not limited; step (a3) ​​can be performed first, and conversely, step (a4) can be performed first, and furthermore, steps (a3) ​​and (a4) can be performed simultaneously.

[0011] In the heat-pressing step (a5), by heat-pressing the first adhesive film, the conductive particles of the first adhesive film can electrically connect the first electrode of the electronic component to the first metal foil layer, and the adhesive layer of the first adhesive film is cured to serve as a first cured adhesive layer. Similarly, by heat-pressing the second adhesive film, the conductive particles of the second adhesive film can electrically connect the second electrode of the electronic component to the second metal foil layer, and the adhesive layer of the second adhesive film is cured to serve as a second cured adhesive layer. At this time, since conductive layers on both sides of the electronic component are formed using an adhesive film containing conductive particles, complex procedures such as laser-based drilling, plating layer formation, and etching-based electrode formation on both sides of the electronic component are eliminated, and conductive layers connecting the electrodes separated in the stacking direction can be easily formed. As a result, according to this manufacturing method, the manufacturing method of the substrate built into the component can be further simplified.

[0012] In the manufacturing method of the substrate built into the aforementioned component, the ratio of the surface roughness Rz of at least one of the first and second metal foil layers to the average particle size of the conductive particles on the side where it is bonded to the corresponding adhesive layer can be 0.05 to 3. In this case, compared to the case where the ratio of the surface roughness Rz of the adhesive layer to the average particle size of the conductive particles is greater than 3, the conductive particles can be more reliably flattened into a flat shape during heat pressing, thereby increasing the contact area between the conductive particles and the metal foil layer and the electrodes of the electronic component. As a result, the electrical conductivity between the metal foil layer, which has been processed into a wiring pattern or wiring, and the electrodes of the electronic component can be stabilized by the conductive particles. Furthermore, this ratio can be expressed as surface roughness Rz / average particle size.

[0013] In the manufacturing method of the substrate built into the aforementioned component, the surface roughness Rz of the side of at least one of the first and second metal foil layers that is bonded to the corresponding adhesive layer can be 20 μm or less. In this case, compared to the case where the surface roughness of the metal foil layer on the adhesive layer side is rough, the conductive particles can be more reliably flattened into a flat shape during heat pressing, thereby increasing the contact area between the conductive particles and the metal foil layer and the electrodes of the electronic component. As a result, the electrical conductivity between the metal foil layer, which has been processed into a wiring pattern or wiring, and the electrodes of the electronic component can be stabilized by the conductive particles.

[0014] In the above-mentioned method for manufacturing a substrate with a built-in component, step (a) of providing an intermediate component may further include step (a6), in which at least one of the first metal foil layer and the second metal foil layer is etched to form an outer electrode of the intermediate component.

[0015] The manufacturing method of the aforementioned component's built-in substrate may further include step (d), in which a first metal foil layer is formed on the first insulating resin layer formed on the first surface of the intermediate member, or a through-hole conductor extends from the first metal foil layer to the processed outer electrode.

[0016] In the manufacturing method of the substrate built into the above-mentioned component, the ratio of the surface roughness Rz of the corresponding cured adhesive layer side of at least one of the first and second metal foil layers to the average particle size of the conductive particles can be 0.05 to 3. In this case, compared to the case where the ratio of the surface roughness Rz of the cured adhesive layer to the average particle size of the conductive particles is greater than 3, the conductive particles can be more reliably flattened into a flat shape, thereby increasing the contact area between the conductive particles and the metal foil layer and the electrodes of the electronic component. As a result, the electrical conductivity between the metal foil layer, which becomes a wiring pattern or wiring after processing, and the electrodes of the electronic component can be stabilized.

[0017] In the manufacturing method of the substrate built into the above-mentioned component, the surface roughness Rz of the side of the cured adhesive layer corresponding to at least one of the first and second metal foil layers can be 20 μm or less. In this case, compared to the case where the surface roughness of the metal foil layer side is rough, the conductive particles can be more reliably flattened into a flat shape, thereby increasing the contact area between the conductive particles and the metal foil layer and the electrodes of the electronic component. As a result, the electrical conductivity between the metal foil layer, which is processed into a wiring pattern or wiring, and the electrodes of the electronic component can be stabilized. In this case, the surface roughness Rz of the corresponding cured adhesive layer side can be 0.5 μm or more and 5.0 μm or less, or 0.5 μm or more and 10 μm or less.

[0018] The manufacturing method of the aforementioned component's built-in substrate may further include step (c), in which a second insulating resin layer is formed on a second surface of the intermediate member opposite to the first surface. At this time, forming the first insulating resin layer on the first surface of the intermediate member while simultaneously forming the second insulating resin layer on the second surface opposite to it can suppress warping and other defects caused by the insulating resin layers.

[0019] Furthermore, as another aspect, the present invention relates to a component-in-place substrate. This component-in-place substrate includes: an intermediate member comprising: an electronic component having a first electrode disposed on a first surface; a first conductive layer disposed on the first surface of the electronic component to cover the first electrode; and a first insulating resin layer formed on the first surface of the intermediate member. The first conductive layer includes: a first cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition; and a first metal foil layer disposed on the first cured adhesive layer and on the side opposite to the electronic component. The conductive particles of the first cured adhesive layer electrically connect the first electrode of the electronic component to the first metal foil layer.

[0020] In the embedded substrate of this component, the first conductive layer of the intermediate component is composed of a first cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition, and a first metal foil layer. The conductive particles of the first cured adhesive layer electrically connect the first electrode of the electronic component to the first metal foil layer. In this case, since the intermediate component including the electronic component is simplified, the structure of the embedded substrate of the component can be simplified.

[0021] In the aforementioned component-in-the-substrate, the intermediate member further includes a second conductive layer disposed on a second surface of the electronic component opposite to the first surface, allowing a second electrode to be disposed on the second surface of the electronic component opposite to the first surface. The second conductive layer comprises: a second cured adhesive layer containing a cured adhesive composition including conductive particles; and a second metal foil layer disposed on the second cured adhesive layer on the surface opposite to the electronic component. The conductive particles of the second cured adhesive layer electrically connect the second electrode of the electronic component to the second metal foil layer. In this case, since the intermediate member including the electronic component is further simplified, the structure of the component-in-the-substrate can be simplified. Furthermore, since the same cured adhesive layer is disposed on both sides of the electronic component, the uniformity in the lamination direction becomes good, and uneven expansion can be suppressed even in the event of thermal expansion within the component-in-the-substrate.

[0022] The built-in substrate of the aforementioned component may also include a second insulating resin layer formed on a second surface opposite to the first surface of the intermediate member. In this case, while the first insulating resin layer is formed on the first surface of the intermediate member, the second insulating resin layer is formed on the second surface opposite to it, which can suppress warping and other issues caused by each insulating resin layer. [Invention Effects]

[0023] According to the present invention, the manufacturing method of the substrate built into the component can be further simplified. Simple Explanation of the Diagram

[0024] Figure 1 is a cross-sectional view of a component-integrated substrate according to one embodiment of the present invention. Figure 2 is a cross-sectional view of the adhesive film used in manufacturing the substrate of the part shown in Figure 1. Figures 3(a) to (d) are cross-sectional views used to sequentially illustrate the method of manufacturing the embedded substrate of the part shown in Figure 1. Figures 4(a) to (c) are cross-sectional views used to sequentially illustrate the method of manufacturing the embedded substrate of the part shown in Figure 1, and to show the subsequent steps in Figure 3. Figures 5(a) to (d) are cross-sectional views used to sequentially illustrate conventional methods for manufacturing components with built-in substrates. Figures 6(a) to (c) are cross-sectional views used to sequentially illustrate the conventional method of manufacturing a component with a built-in substrate, and show the subsequent steps in Figure 5. Implementation

[0025] Hereinafter, with reference to the drawings, a component-in-the-board substrate and a method for manufacturing the component-in-the-board substrate according to one embodiment of the present invention will be described. In the following description, the same or equivalent parts will be labeled with the same component symbols, and repeated descriptions will be omitted. Furthermore, regarding positional relationships such as top, bottom, left, and right, unless otherwise specified, the positional relationships shown in the drawings will be used. Moreover, the scale of the drawings is not limited to the scale shown in the drawings.

[0026] Figure 1 is a cross-sectional view of a component-in-the-board substrate according to one embodiment of the present invention. As shown in Figure 1, the component-in-the-board substrate 1 is composed of an intermediate member 2 including an electronic component 10, a first conductive layer 20 and a second conductive layer 30, a first insulating resin layer 40 and a second insulating resin layer 50. The electronic component 10 is, for example, an IC chip or other electronic component, having a first surface 13 and a second surface 14 on the opposite side. A first electrode 11 is provided on the first surface 13, and a second electrode 12 is provided on the second surface 14 (see Figure 3(a)). The electronic component 10 can be other electronic components such as a capacitor, or it can be a structure in which the conductive layer and the insulating resin layer are provided only on one surface (e.g., the first surface 13).

[0027] The first conductive layer 20 includes a conductive region of the first electrode 11 on the first surface 13 of the electronic component 10, which is disposed thereon to cover the first electrode 11 on the first surface 13, and electrically connects one electrode to another in the stacking direction. The first conductive layer 20 has: a first cured adhesive layer 23 containing a cured adhesive layer 22 comprising conductive particles 21 and a cured adhesive composition; and a first metal foil layer 24 (internal electrode) disposed on the first cured adhesive layer 23 on the side opposite to the electronic component 10. The first metal foil layer 24 can be a metal foil layer before processing, or a metal foil layer after processing into an electrode pattern, etc. In the first conductive layer 20, as described later, by heating and pressing the first adhesive film 60 (see FIG. 3(b)), the conductive particles 61a of the first adhesive film 60 electrically connect the first electrode 11 of the electronic component 10 to the first metal foil layer 24, and the adhesive layer 62 of the first adhesive film 60 is thermally cured (see FIG. 3(c)). That is, the adhesive layer portion of the first cured adhesive layer 23 becomes a cured product formed by curing a thermosetting adhesive composition. Regarding the conductive particles 21, there are no particular limitations as long as they are conductive particles; they can be metal particles composed of metals such as Au, Ag, Ni, Cu, and solder, or conductive carbon particles composed of conductive carbon. The conductive particles 21 can be coated conductive particles having a core comprising non-conductive glass, ceramic, or plastic (polystyrene, etc.) and a coating layer comprising the aforementioned metal or conductive carbon and covering the core. Furthermore, the conductive particles 21 can be insulating coated conductive particles having the aforementioned metal particles, conductive carbon particles, or coated conductive particles and an insulating layer comprising an insulating material such as resin and covering the surface of the particles.

[0028] The second conductive layer 30 includes a conductive area of ​​the second electrode 12 on the second surface 14 of the electronic component 10, which is disposed on the second surface 14 to cover the second electrode 12 on the second surface 14, and electrically connects one electrode to another in the stacking direction. The second conductive layer 30 has: a second cured adhesive layer 33 containing a cured adhesive layer 32 comprising conductive particles 31 and a cured adhesive composition; and a second metal foil layer 34 (internal electrode) disposed on the second cured adhesive layer 33 on the side opposite to the electronic component 10. The second metal foil layer 34 can be a metal foil layer before processing, or a metal foil layer after processing into an electrode pattern, etc. In the second conductive layer 30, as described later, by heating and pressing the second adhesive film 70 (see FIG. 3(b)), the conductive particles 71a of the second adhesive film 70 electrically connect the second electrode 12 of the electronic component 10 to the second metal foil layer 34, and the adhesive layer 72 of the second adhesive film 70 is thermally cured (see FIG. 3(c)). That is, the adhesive layer portion of the second cured adhesive layer 33 becomes a cured product formed by curing a thermosetting adhesive composition. Regarding the conductive particles 31, there are no particular limitations as long as they are conductive particles; they can be metal particles composed of metals such as Au, Ag, Ni, Cu, and solder, or conductive carbon particles composed of conductive carbon. The conductive particles 31 can be coated conductive particles having a core containing non-conductive glass, ceramic, or plastic (polystyrene, etc.) and a coating layer containing the aforementioned metal or conductive carbon and covering the core. Furthermore, the conductive particles 31 can be insulating coated conductive particles having the aforementioned metal particles, conductive carbon particles, or coated conductive particles and an insulating layer containing an insulating material such as resin and covering the surface of the particles.

[0029] The first insulating resin layer 40 is formed on the first surface 3 of the intermediate member 2, and includes an insulating layer 41, a through-hole conductor 42, and an external electrode 43. The insulating layer 41 is composed of, for example, resins such as epoxy and inorganic particles such as glass. The insulating layer 41 may include reinforcing materials such as glass cloth. The through-hole conductor 42 is a conductive member used to electrically connect the first metal foil layer 24 (internal electrode) of the intermediate member 2 to the external electrode 43, and is formed by plating filling the through-holes provided in the insulating layer 41. The external electrode 43 is electrically connected to the upper end of the through-hole conductor 42.

[0030] The second insulating resin layer 50 is an insulating layer formed on the second surface 4 of the intermediate member 2. The second insulating resin layer 50 is composed, for example, of resins such as epoxy and inorganic particles such as glass. The second insulating resin layer 50 may contain reinforcing materials such as glass cloth. Furthermore, like the first insulating resin layer 40, the second insulating resin layer 50 may have through-hole conductors and external electrodes.

[0031] Next, referring to Figures 2 to 4, the manufacturing method of the component-in-place substrate described above will be explained. Figure 2 is a cross-sectional view showing the adhesive film used in manufacturing the component-in-place substrate shown in Figure 1. Figures 3(a) to (d) are cross-sectional views used to sequentially explain the method of manufacturing the component-in-place substrate shown in Figure 1. Figures 4(a) to (c) are cross-sectional views used to sequentially explain the method of manufacturing the component-in-place substrate shown in Figure 1, and show the subsequent steps in Figure 3. The manufacturing method of the component-in-the-substrate of this embodiment includes: step (a) providing an intermediate component, the intermediate component comprising: an electronic component having a first electrode and a second electrode disposed on a first surface and a second surface; a first conductive layer disposed on the first surface of the electronic component to cover the first electrode; and a second conductive layer disposed on the second surface of the electronic component to cover the second electrode; step (b) forming a first insulating resin layer on the first surface of the intermediate component; step (c) forming a second insulating resin layer on the second surface of the intermediate component opposite to the first surface; and step (d) forming a first metal foil layer on the first insulating resin layer formed on the first surface of the intermediate component or a through-hole conductor extending from the first metal foil layer to a processed outer electrode. The following is a detailed description. Furthermore, the order of steps (a) to (d) is not limited to the order described above, and the order can be appropriately changed. For example, it can be done in the order of steps (a), (b), (c), and (d), or in the order of steps (a), (c), (b), and (d), or in the order of steps (a), (b), (d), and (c).

[0032] [Step (a) of providing intermediate components] Step (a) of providing the intermediate component 2 includes: a step of preparing the electronic component 10 (a1); a step of preparing the first adhesive film (a2); a step of attaching the first adhesive film to the first surface of the electronic component to cover the first electrode (a3); a step of heating and pressing the first adhesive film onto the electronic component (a4); and a step of etching the first metal foil layer to form the outer electrode of the intermediate component (a5). Furthermore, the outer electrode can be formed on the second surface of the intermediate component using the same method.

[0033] In step (a1) of preparing electronic components, as shown in Figure 3(a), an electronic component 10 is prepared, on the first surface 13 and the second surface 14, having a first electrode 11 and a second electrode 12. The electronic component 10 is, for example, an IC chip or other electronic component. Furthermore, a plurality of first electrodes 11 and second electrodes 12 may be provided.

[0034] In step (a2) of preparing the adhesive film, as shown in FIG2, a first adhesive film 60 is prepared, which has: a first adhesive layer 63, an adhesive layer 62 containing a plurality of conductive particles 61 and an adhesive composition in which the conductive particles 61 are dispersed; and a first metal foil layer 64 disposed on the first adhesive layer 63. Similarly, a second adhesive film 70 is prepared, which has: a second adhesive layer 73, an adhesive layer 72 containing a plurality of conductive particles 71 and an adhesive composition in which the conductive particles 71 are dispersed; and a second metal foil layer 74 disposed on the second adhesive layer 73 on the side opposite to the electronic component 10. Such a first adhesive film 60 and a second adhesive film 70 are components for wiring. The adhesive composition of adhesive layer 62 and adhesive layer 72 is an adhesive composition containing thermosetting insulating resins such as epoxy resin, phenolic resin, and acrylic resin, and is formulated by dispersing conductive particles 61 and 71 with a particle size of several μm in it.

[0035] From the viewpoint of excellent dispersibility and conductivity, the average particle size Dp of conductive particles 61 and 71 can be 1 μm or more, 2 μm or more, or 5 μm or more. From the viewpoint of excellent dispersibility and conductivity, the average particle size Dp of conductive particles can be 50 μm or less, 30 μm or less, or 20 μm or less. From the above viewpoints, the average particle size Dp of conductive particles can be 1~50 μm, 5~30 μm, 5~20 μm, or 2~20 μm.

[0036] The maximum particle size of conductive particles 61 and 71 can be smaller than the minimum spacing (shortest distance between adjacent electrodes) of the wiring pattern. From the viewpoint of excellent dispersibility and conductivity, the maximum particle size of conductive particles 61 and 71 can be 1 μm or more, 2 μm or more, or 5 μm or more. From the viewpoint of excellent dispersibility and conductivity, the maximum particle size of conductive particles can be 50 μm or less, 30 μm or less, or 20 μm or less. From the above viewpoints, the maximum particle size of conductive particles can be 1 to 50 μm, 2 to 30 μm, or 5 to 20 μm.

[0037] In this specification, for any 300 particles, the particle size was measured using a scanning electron microscope (SEM). The average particle size obtained was taken as the average particle size Dp, and the maximum value obtained was taken as the maximum particle size. In addition, in cases where the particle has protrusions or the particle shape is not spherical, the particle size was taken as the diameter of the circle tangent to the particle in the SEM image.

[0038] The first metal foil layer 64 and the second metal foil layer 74 are, for example, copper foil, aluminum foil, nickel foil, stainless steel, titanium, or platinum. The surface roughness Rz of the side 65 of the first metal foil layer 64 that is bonded to the first adhesive layer 63 can be 20 μm or less, or it can be 0.5 μm or more and 5.0 μm or less, or it can be 0.5 μm or more and 10 μm or less. Similarly, the surface roughness Rz of the side 75 of the second metal foil layer 74 that is bonded to the second adhesive layer 73 can be 20 μm or less, or it can be 0.5 μm or more and 5.0 μm or less, or it can be 0.5 μm or more and 10 μm or less.

[0039] Surface roughness Rz refers to the ten-point average roughness Rzjis measured according to the method specified in JIS standard (JIS B 0601-2001), and refers to the value measured using a commercially available surface roughness shape measuring instrument. For example, it can be measured using a Nano Search Microscope (manufactured by SHIMADZU CORPORATION, "SFT-3500").

[0040] Hereinafter, the relationships between the surface roughness Rz of the surface 65 of the first metal foil layer 64 and the average particle size Dp of the conductive particles 61, and the relationships between the surface roughness Rz of the surface 75 of the second metal foil layer 74 and the average particle size Dp of the conductive particles 71 will be explained. In this embodiment, the ratio of the surface roughness Rz of the surface 65 of the metal foil layer 64 to the average particle size Dp of the conductive particles 61, and the ratio of the surface roughness Rz of the surface 75 of the metal foil layer 74 to the average particle size Dp of the conductive particles 71, i.e., "surface roughness / average particle size", can be 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.1 or more, 0.2 or more, 0.3 or more, 0.5 or more, or 1 or more. Furthermore, the ratio of the surface roughness Rz of the surface 65 of the metal foil layer 64 to the average particle size Dp of the conductive particles 61, and the ratio of the surface roughness Rz of the surface 75 of the metal foil layer 74 to the average particle size Dp of the conductive particles 71, i.e., "surface roughness / average particle size", can be 3 or less, 2 or less, 1.7 or less, or 1.5 or less, respectively. For example, the ratio of the surface roughness Rz of the surface 65 of the metal foil layer 64 to the average particle size Dp of the conductive particles 61, and the ratio of the surface roughness Rz of the surface 75 of the metal foil layer 74 to the average particle size Dp of the conductive particles 71, i.e., "surface roughness / average particle size", can be 0.05 or more and 3 or less, and more specifically, 0.06 or more and 2 or less, respectively. In this embodiment, the surface roughness Rz of the metal foil layer 64 and the average particle size Dp of the conductive particles 61 can be managed by the ratio of the surface roughness Rz of the metal foil layer 64 and the average particle size Dp of the conductive particles 71, and the ratio of the surface roughness Rz of the metal foil layer 74 and the average particle size Dp of the conductive particles 71, i.e., "surface roughness / average particle size", being in the range of 0.05 to 3.

[0041] Furthermore, it is known that when the ratio of the surface roughness Rz of the side 65 of the metal foil layer 64 bonded to the adhesive layer 63 to the average particle size of the conductive particles 61, and the ratio of the surface roughness Rz of the side 75 of the metal foil layer 74 bonded to the adhesive layer 73 to the average particle size of the conductive particles 71, is between 0.05 and 3, compared to the case where the ratio is greater than 3, the conductive particles 61 and 71 can be more reliably flattened into a flat shape, thereby increasing the contact area between the conductive particles 61 and the metal foil layer 64, and the contact area between the conductive particles 71 and the metal foil layer 74. Therefore, by setting the ratio of surface roughness Rz to average particle size within the above-mentioned range, the electrical conductivity between the metal foil layers 64 and 74, which are processed into wiring patterns or wirings, and other wiring patterns or wirings bonded to the adhesive layers 63 and 73 can be stabilized.

[0042] In steps (a3) ​​and (a4) of applying the adhesive film, as shown in Figure 3(b), a first adhesive film 60 is applied to the first surface 13 of the electronic component 10 to cover the first electrode 11 on the first surface 13. Similarly, a second adhesive film 70 is applied to the second surface 14 of the electronic component 10 to cover the second electrode 12 on the second surface 14. At this time, the first metal foil layer 64 and the second metal foil layer 74 are configured to be located on the opposite side of the electronic component 10.

[0043] In the step (a5) of heating and pressing the adhesive films, as shown in Figure 3(c), the first adhesive film 60 and the second adhesive film 70 are heated and pressed onto the electronic component 10 and then bonded. By heating and pressing the first adhesive film 60, the conductive particles 61a of the first adhesive film 60 electrically connect the first electrode 11 of the first surface 13 of the electronic component 10 to the first metal foil layer 64, and the adhesive layer 62 of the first adhesive film 60 is cured to form the first cured adhesive layer 60a (20). Similarly, by heating and pressing the second adhesive film 70, the conductive particles 71a of the second adhesive film 70 electrically connect the second electrode 12 of the second surface 14 of the electronic component 10 to the second metal foil layer 74, and the adhesive layer 72 of the second adhesive film 70 is cured to form the second cured adhesive layer 70a (30). The heating and pressing of the first adhesive film 60 and the second adhesive film 70 can be performed simultaneously or sequentially. Furthermore, if the ratio of the surface roughness Rz of the side of the metal foil layer 64 that is bonded to the adhesive layer 63 to the average particle size of the conductive particles 61, the ratio of the surface roughness Rz of the side of the metal foil layer 74 that is bonded to the adhesive layer 73 to the average particle size of the conductive particles 71 is 0.05 to 3, or the surface roughness Rz of the side of the first metal foil layer 64 and the side of the second metal foil layer 74 is 20 μm or less, it is easier to flatten each conductive particle 61 and 71 into a flat shape, thereby stabilizing the conduction of the electronic component 10.

[0044] Next, in step (a6) of forming the outer electrode of the intermediate component, as shown in Figure 3(d), the first metal foil layer 64 of the first cured adhesive layer 60a is etched to form a predetermined electrode 64a (24). Similarly, the second metal foil layer 74 of the second cured adhesive layer 70a is etched to form a predetermined electrode 74a (34). Thereby, a through-hole electrode connected to the electronic component 10 is formed in the intermediate component 2. In addition, in the above step (a), the conductive layer of the electronic component 10 is formed using an adhesive film containing conductive particles. Therefore, it is not necessary to perform complex procedures such as conventional laser-based drilling, plating layer formation, and etching-based electrode formation on the outside of the electronic component. Instead, it is possible to easily form each conductive layer connected between electrodes separated in the stacking direction. As a result, according to this manufacturing method, the manufacturing method of the component-integrated substrate 1 can be simplified.

[0045] If step (a) of providing the intermediate component is completed, in steps (b) and (c) of forming the insulating resin layer, as shown in FIG4(a), a first insulating resin layer 40 is formed on the first surface 3 of the intermediate component 2, and a second insulating resin layer 50 is formed on the second surface 4 of the intermediate component 2 opposite to the first surface 3. Subsequently, a hole 44 is formed at a predetermined location in the first insulating resin layer 40 by means of a laser or the like. The hole 44 is a hole that extends from the outside of the first insulating resin layer 40 to the electrode (first metal foil layer 24) of the intermediate component 2. Subsequently, as shown in FIG4(b), the hole 44 is filled with plating to form a through-hole conductor 42 and an electrode layer 45. Furthermore, the electrode layer 45 is etched to form a predetermined external electrode 43, obtaining the component-in-place substrate 1 shown in FIG4(c).

[0046] In the manufacturing method of the component-in-the-substrate 1 of this embodiment, the first conductive layer 20 of the intermediate component 2 provided in step (a) is composed of a first cured adhesive layer 23 having a cured adhesive layer 22 (62a) containing conductive particles 21 (61a) and a cured adhesive composition, and a first metal foil layer 24. The conductive particles 21 of the first cured adhesive layer 23 electrically connect the first electrode 11 of the electronic component 10 to the first metal foil layer 24. Similarly, the second conductive layer 30 of the intermediate component 2 is composed of a second cured adhesive layer 33 having a cured adhesive layer 32 (72a) containing conductive particles 31 (71a) and a cured adhesive composition, and a second metal foil layer 34. The conductive particles 31 of the second cured adhesive layer 33 electrically connect the second electrode 12 of the electronic component 10 to the second metal foil layer 34. Thus, in the manufacturing method of this embodiment, the intermediate component 2, including the electronic component 10, can be configured with a simplified structure, thereby simplifying the manufacturing method of the component-integrated substrate 1 compared to the past.

[0047] Furthermore, in the manufacturing method of the component-in-the-substrate of this embodiment, the ratio of the surface roughness Rz of at least one of the first metal foil layer 64 and the second metal foil layer 74 on the side where it is bonded to the adhesive layer to the average particle size of the conductive particles 61 and 71 can be 0.05 to 3. Alternatively, the surface roughness Rz of at least one of the first metal foil layer 64 and the second metal foil layer 74 on the side where it is bonded to the corresponding adhesive layers 63 and 73 can be 20 μm or less. In this case, compared with the case where the ratio of surface roughness Rz to average particle size is greater than 3, or the case where the surface roughness of the metal foil layer on the adhesive layer side is rough, the conductive particles 61 and 71 can be more reliably flattened into a flat shape during heat pressing, thereby increasing the contact area between the conductive particles 61a and 71a and the metal foil layer and the electrodes of the electronic component. In other words, when the ratio of surface roughness Rz to average particle size is greater than 3, or when the surface of the metal foil layer on the adhesive layer side is rough, conductive particles may enter the rough surface shape, making it impossible to fully flatten the conductive particles (e.g., flatten them into a flat shape) during heat pressing, resulting in unstable conductivity. However, by setting the ratio of surface roughness Rz to average particle size to 0.05~3, or by setting the surface roughness Rz of the metal foil layer to 20μm or less, the conductive particles can be reliably flattened during heat pressing. As a result, the conductive particles can stabilize the electrical conductivity between the metal foil layer, which has been processed into a wiring pattern or wiring, and the electrodes of the electronic component.

[0048] Furthermore, in the component-in-the-substrate 1 of this embodiment, the first conductive layer 20 of the intermediate component 2 is composed of a first cured adhesive layer 23 having a cured adhesive layer 22 containing conductive particles 21 and a cured adhesive composition, and a first metal foil layer 24. The conductive particles 21 of the first cured adhesive layer 23 electrically connect the first electrode 11 of the electronic component 10 to the first metal foil layer 24. Similarly, the second conductive layer 30 of the intermediate component 2 is composed of a second cured adhesive layer 33 having a cured adhesive layer 32 containing conductive particles 31 and a cured adhesive composition, and a second metal foil layer 34. The conductive particles 31 of the second cured adhesive layer 33 electrically connect the second electrode 12 of the electronic component 10 to the second metal foil layer 34. In this case, since the intermediate component 2 including the electronic component 10 is simplified by using an adhesive film, the structure of the component-in-the-substrate 1 can be simplified. Furthermore, since the same cured adhesive layer is provided on both sides of the electronic component 10, the uniformity in the stacking direction becomes good, and even in the event of thermal expansion in the built-in substrate 1 of the component, uneven expansion can be suppressed.

[0049] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the above embodiments and can be applied to various embodiments. For example, in the above embodiments, as shown in FIG2, the adhesive films 60 and 70 have a structure in which conductive particles 61 and 71 are randomly or evenly dispersed in the adhesive layers 63 and 73, but the conductive particles 61 and 71 can be arranged adjacent to (biased towards) the metal foil layers 64 and 74. In this case, the conductive particles 61 and 71 are not exposed on the side opposite to the metal foil layers 64 and 74 in the adhesive layers 63 and 73, and the thickness of the portion of the adhesive layer 62 and 72 existing between the conductive particles 61 and 71 and the surfaces 65 and 75 of the metal foil layers 64 and 74 can be greater than 0 μm and less than 1 μm. In this case, since the conductive particles 61 and 71 are arranged adjacent to the metal foil layers 64 and 74, the conductive particles 61 and 71 can be more reliably flattened into a flat shape by means of the metal foil layers 64 and 74. Furthermore, by having conductive particles 61 and 71 locally present on the sides of the metal foil layers 64 and 74, the replenishment rate of conductive particles 61 and 71 to wiring (electrodes) can be increased. That is, the conductivity can be made more stable.

[0050] Furthermore, adhesive layers 62 and 72 can be formed by dividing them into a first adhesive layer adjacent to the metal foil layers 64 and 74 and a second adhesive layer separate from the metal foil layers 64 and 74. The adhesive composition constituting the first adhesive layer and the second adhesive layer can be the same as the adhesive composition constituting the adhesive layers 62 and 72 described above. However, the conductive particles 61 and 71 can be dispersed only in the first adhesive layer and not dispersed in the second adhesive layer, i.e., the second adhesive layer does not contain conductive particles 61 and 71. In this case, similarly as described above, since the conductive particles 61 and 71 are arranged adjacent to the metal foil layers 64 and 74, the conductive particles 21 can be more reliably flattened into a flat shape by the metal foil layers 64 and 74. Furthermore, by making the conductive particles 61 and 71 biased towards the metal foil layers 64 and 74, the replenishment rate of the conductive particles 61 and 71 to the wiring (electrodes), etc., can be improved. That is, it can make the conduction more stable.

[0051] 1: The component has a built-in substrate 2: Intermediate components 3: Page 1 4: Page 2 10: Electronic components 11: First electrode 12: Second electrode 13: Page 1 14: Page 2 20: First conductive layer 21,61,61a: Conductive particles 22: Curing adhesive layer 23: First cured adhesive layer 24,64: First metal foil layer 31,71,71a: Conductive particles 32: Curing adhesive layer 33: Second cured adhesive layer 34,74: Second metal foil layer 40: First insulating resin layer 42: Through-hole conductor 50: Second insulating resin layer 60: First membrane adhesion 62: Adhesive layer 63: First adhesive layer 65, 75: Face 70: Second adhesion membrane 72: Adhesive layer 73: Second adhesive layer

Claims

1. A method for manufacturing a substrate integrated into a component, comprising: The step of providing an intermediate component, wherein the intermediate component comprises: an electronic component having a first electrode disposed on a first surface; The first conductive layer is disposed on the first surface of the aforementioned electronic component to cover the aforementioned first electrode; and the first insulating resin layer is formed on the first surface of the aforementioned intermediate member. The first conductive layer comprises: a first cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition; and a first metal foil layer disposed on the first cured adhesive layer and on the side opposite to the aforementioned electronic component. The conductive particles of the first cured adhesive layer electrically connect the aforementioned first electrode of the aforementioned electronic component to the aforementioned first metal foil layer. The ratio of the surface roughness Rz of the surface of the first metal foil layer corresponding to the side of the aforementioned cured adhesive layer to the average particle size of the aforementioned conductive particles is 0.05 to 3, or the surface roughness Rz of the surface of the first metal foil layer corresponding to the side of the aforementioned cured adhesive layer is 20 μm or less.

2. A method for manufacturing a component-in-the-substrate as claimed in claim 1, wherein the aforementioned intermediate component further comprises a second conductive layer disposed on a second surface of the aforementioned electronic component opposite to the aforementioned first surface, and a second electrode disposed on the second surface of the aforementioned electronic component opposite to the aforementioned first surface. The aforementioned second conductive layer comprises: a second cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition; and a second metal foil layer disposed on the aforementioned second cured adhesive layer and on the surface opposite to the aforementioned electronic component. The aforementioned conductive particles of the aforementioned second cured adhesive layer electrically connect the aforementioned second electrode of the aforementioned electronic component to the aforementioned second metal foil layer.

3. A method for manufacturing a component-integrated substrate as described in claim 2, wherein the step of providing the aforementioned intermediate component includes: The steps for preparing the aforementioned electronic components; The first step in preparing the adhesive membrane; The steps of attaching the first adhesive film to the first surface of the aforementioned electronic component to cover the first electrode; and the steps of heating and pressing the first adhesive film onto the aforementioned electronic component, wherein the first adhesive film has: a first adhesive layer containing an adhesive layer comprising conductive particles and an adhesive composition, wherein the conductive particles are dispersed in the adhesive composition; and a first metal foil layer disposed on the first adhesive layer and on the side opposite to the aforementioned electronic component. In the aforementioned heating and pressing step, by heating and pressing the first adhesive film, the conductive particles of the first adhesive film electrically connect the first electrode of the aforementioned electronic component to the first metal foil layer, and the adhesive layer of the first adhesive film is cured to become the aforementioned first cured adhesive layer.

4. A method for manufacturing a component-integrated substrate as described in claim 2, wherein the step of providing the aforementioned intermediate component includes: The steps for preparing the aforementioned electronic components; Steps for preparing the first and second adhesive films; The steps include: adhering the first adhesive film to the first surface of the aforementioned electronic component to cover the first electrode; adhering the second adhesive film to the second surface of the aforementioned electronic component to cover the second electrode; and heating and pressing the first adhesive film and the second adhesive film onto the aforementioned electronic component. The first adhesive film comprises: a first adhesive layer containing conductive particles and an adhesive composition in which the conductive particles are dispersed; and a first metal foil layer disposed on the first adhesive layer on the side opposite to the aforementioned electronic component. The second adhesive film comprises: a second adhesive layer containing conductive particles and an adhesive composition in which the conductive particles are dispersed; and a second metal foil layer disposed on the second adhesive layer on the side opposite to the aforementioned electronic component. In the aforementioned heat-pressing step, by heat-pressing the aforementioned first adhesive film, the aforementioned conductive particles of the aforementioned first adhesive film electrically connect the aforementioned first electrode of the aforementioned electronic component to the aforementioned first metal foil layer, and the aforementioned adhesive layer of the aforementioned first adhesive film is cured to serve as the aforementioned first cured adhesive layer. By heat-pressing the aforementioned second adhesive film, the aforementioned conductive particles of the aforementioned second adhesive film electrically connect the aforementioned second electrode of the aforementioned electronic component to the aforementioned second metal foil layer, and the aforementioned adhesive layer of the aforementioned second adhesive film is cured to serve as the aforementioned second cured adhesive layer.

5. A method for manufacturing a component-in-the-substrate as described in claim 3 or claim 4, wherein the ratio of the surface roughness Rz of at least one of the aforementioned first metal foil layer and the aforementioned second metal foil layer to the surface of the side to which the aforementioned adhesive layer is attached and the average particle size of the aforementioned conductive particles is 0.05 to 3.

6. A method for manufacturing a component-in-the-substrate as described in claim 3 or claim 4, wherein the surface roughness Rz of at least one of the aforementioned first metal foil layer and the aforementioned second metal foil layer on the side of the metal foil layer that is bonded to the corresponding aforementioned adhesive layer is 20 μm or less.

7. A method for manufacturing a component-in-the-substrate as described in claim 3 or claim 4, wherein the step of providing the aforementioned intermediate component further includes the step of etching at least one of the aforementioned first metal foil layer and the aforementioned second metal foil layer to form an outer electrode of the aforementioned intermediate component.

8. A method for manufacturing a component-in-the-substrate as described in claim 7, further comprising the steps of: forming the aforementioned first metal foil layer on the first surface of the aforementioned intermediate member, or extending from the aforementioned first metal foil layer to a through-hole conductor of the processed aforementioned outer electrode.

9. A method for manufacturing a component-in-the-substrate as described in any one of claims 2 to 4, wherein the ratio of the surface roughness Rz of the surface of the second metal foil layer corresponding to the previously described cured adhesive layer to the average particle size of the aforementioned conductive particles is 0.05 to 3.

10. A method for manufacturing a component-in-the-substrate as described in any one of claims 2 to 4, wherein the surface roughness Rz of the side of the metal foil layer corresponding to the previously described cured adhesive layer of the second metal foil layer is 20 μm or less.

11. A method for manufacturing a component-in-the-substrate as described in claim 10, wherein the surface roughness Rz of the surface on the side of the aforementioned cured adhesive layer is 0.5 μm or more and 10 μm or less.

12. A method for manufacturing a component-in-the-substrate as described in any one of claims 1 to 4, further comprising the step of forming a second insulating resin layer on a second surface of the aforementioned intermediate member opposite to the aforementioned first surface.

13. A component-in-the-substrate comprising: an intermediate member, the intermediate member comprising: an electronic component having a first electrode disposed on a first surface; a first conductive layer disposed on the first surface of the electronic component to cover the first electrode; and a first insulating resin layer formed on the first surface of the intermediate member, the first conductive layer comprising: a first cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition; and a first metal foil layer disposed on the first cured adhesive layer and on a surface opposite to the electronic component, the conductive particles of the first cured adhesive layer electrically connecting the first electrode of the electronic component to the first metal foil layer, the ratio of the surface roughness Rz of the surface of the first metal foil layer corresponding to the cured adhesive layer side to the average particle size of the conductive particles being 0.05 to 3, or the surface roughness Rz of the surface of the first metal foil layer corresponding to the cured adhesive layer side being 20 μm or less.

14. The component-in-the-substrate as claimed in claim 13, wherein the aforementioned intermediate component further comprises a second conductive layer disposed on a second surface of the aforementioned electronic component opposite to the aforementioned first surface, and a second electrode disposed on the second surface of the aforementioned electronic component opposite to the aforementioned first surface, the aforementioned second conductive layer comprising: a second cured adhesive layer containing a cured adhesive layer comprising conductive particles and a cured adhesive composition; and a second metal foil layer disposed on the aforementioned second cured adhesive layer and on the surface opposite to the aforementioned electronic component, wherein the aforementioned conductive particles of the aforementioned second cured adhesive layer electrically connect the aforementioned second electrode of the aforementioned electronic component to the aforementioned second metal foil layer.

15. The component-in-place substrate as described in claim 13 or claim 14, further comprising a second insulating resin layer formed on a second surface of the aforementioned intermediate member opposite to the aforementioned first surface.

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